Japanese Cover--What Is It?

Hello, Does anyone have any information about this cover.Age, use etc.
Many Thanks
David

It's just a little decorative envelope, with the artist's (unreadable) name at lower right. No date or other explanation on it.

It's a picture of the elusive "bunnork". Know to have come from the mating of bunny and a stork, this creature hides in the hollows of rocks and only comes out when there is no nightime. The Japanese government has had these creatures protected for decades. The population once thought to be as high as 1 is now questionable and all educated lycanthopes are hunting to find any sign of another. They are believed to be most populous on the western side of the eastern shore. There is a reward of 10 yen for capturing one and a fine of 10 yen for harboring one in your bathroom.Please report any sightings to the interior ministry!